Operating electric projectile fuses



1929. H. SCHULER ET AL 1,739,921

OPERATING ELECTRIC PROJECTILE FUES Filed Aug. 1927 mvnlm Hermann JcAuZer a d 4715072 6Lez 77Z8 Z DEBENDORE, GERMANY I NN SC'EULER AND ANTON GIETMANN, TO BEEINISCHE METALLWAABEN- UNI) MASCHINENFABRK,

OF UNTERLUSS, GERMANY, ASSIGNORS OF DUSSELDORF- OPERATING ELECTRIC PBOJECTIIE FUSES Application filed August 1, 1927, Serial No. 209,847, and in Germany September 1, 1926.

Our invention relates to means for operating electric fuses for projectiles.

In electric projectile fuses the electric energy required for the ignition of the primer is already present in the projectile before the discharge, in an electric storage device, such as an accumulator or a condenser, or the projectile contains a current producing plant, such as a generator or a cell, which enters into action on or after the shot during the flight of the projectile or only on its impact on the aim, and I produces the required electric energy. The projectile thus carries with it already before the shot and in any condition, the entire energy required to cause the explosion of the bursting charge. If this energy is not present there from the first in the condition required for the ignition, that means as electric energy, the latent energy is transformed automatically after the shot into electric one, without that the operations further enacted and the efi'ects resulting therefrom would permit any further human influence.

Now the method and the means forming the subject-matter of our present invention provide the possibility of imparting to these operations an intentional and determined direction even after the projectile has been fired. According to our invention the electric energy required for initiating the ignition of the primer or for immediately igniting the latter, is transmitted only after the shot and during the flight of the projectile from a source of current separate from the projectile, or only a portion of this required electric energy is transmitted to the igniting device during the flight of the projectile after the shot, whilst the projectile itself carries with it, already before being fired, the remaining portion of the required energy in a latent state in a storage device, and transforms it into active power by means of a generator only during its further flight.

Furthermore, a very reliable guard for the projectile, when still in the gun-barrel or on transport, is thus created, as before the shot till the moment the projectile leaves the muzzle of the barrel it possesses no energy that would cause the explosion of the bursting jectile, which conductor is conductively connected to a source of current and from which the electric igniting device of the projectile receives the required electric energy by a contact action, when passing past said conductor during the flight of the projectile. Or a field of lines of force is arranged beside the path of the projectile, which field produces an induction current in the electric igniting device of the projectile passing through said field after belng fired. According to, whether a proj ectile fitted with an electric fuse is fired that possesses only an electric accumulator or besides the latter a power producingplant, the whole electric-energy required for initiating the i nition of the primer or for immediately ignitmg the latter, is transmitted to the projectile, on only the remainder of energy still wanting.

Preferably that portion of the electric power producing plant serving to charge the electric fuse and arranged outside the projectile and causing a current to flow in the fuse or producing an induction current therein, that is, the contact points or an exciting coil, are arranged in front of the muzzle of the gun-barrel. The charging of the electric fuse thus takes place only after the projectile has already left the gun-barrel. This affords a very reat safety of the fuse when still within t e barrel. It is further obtained by this arrangement, that the charging of the fuse and the mechanical motions eventually tripped therein take place only after the projectile is not longer accelerated or is accelerated still in such a little degree only, that by forces of inertia. .The contact'points or the members producing a field of lines of force, of the plant and arran ed beside the path of the projectile are pre erably rigidly connected with a part of the gun that partakes of the pointingmotions of the latter,

. as for instance with the cradles or with the v This arrangement enables the gun to fire pro jectiles having electric fuses that require different'quantities of electric energy for the ignition of the primer of the bursting charge,

as it permits of the current plant to be adapted to the different conditions and nature of the fuses. Besides, when projectiles are used the setting to different ignition moments of the fuses of which is effected by varying the quantit of the electric energy .Supplied to them, t e possibility is afforded of the fuses being set to different ignition moments by charging and setting of the takes place by means of separate excitation simply varying said current or the strength of said field of the electric plant arranged outside the projectile.

In order to allow of our invention to be more easily understood, a preferred embodiment of the means for carr ing out our method is diagrammatically il ustrated in Fig. 1

of the accompanying drawing in combination with a 11, whilst Fig. 2 diagrammatically shows tie interior of an appurtenant projectile equipped with an electric time fuse.

In the arrangement shown in Fig. 1, the electric fuse by an exciting coil surrounding a section of the path of the projectile. In order to secure this coil against the direct action ofthe propulsive gases, the latter are preferably defiected laterally between themuzzle and the exciting coil, this being obtained by mounting amuzzle brake b on the gun-barrel a,

' which arrangement is of advantage still to obtain other purposes.

The exciting coil 0 is mounted on the cylindrical portion 6 located in front of the baflie wall 6 of-the muzzle brake, and is'connected through a regulating resistance 0! and an amperemeter e to a source of current f. The

" regulating resistance serves to vary the electromotive force supplied to coil 0 and thus to vary the strength of the field of lines of force generated by said coil. The resistance at the gun or sepaclosely behind the guide bunch 9 The ends of this coil h are connected to a second coil i and to a condenser is. An iron core Z is shiftably mounted in the coil 2', which core is partly outside the latter under the actionv of a spring m. The iron core has pivotally connected to it a lever 0 which is mounted on one end for rocking motion in the body of the pro ectile by means of a pivot n. This lever is further pivotally connected on its free end with a shiftable'rack p and abuts. in position of rest on a fixed lug 9 under the action of spring m acting on the iron core Z. The rack p'lias fixed on it a tilting contact piece 9 adapted to interconnect the wires 8 which connect the condenser k with the contact pieces a embedded in the primer 1'. During transportation and until the projectile-is fired, the various parts of the electric pro ectile fuse assume the positions shown in Fig. 2. When fired the contact t which heretofore has been held in open position by means of a spring, not shown, will be moved into the circuit of the condenser is to the coil 72. against the operation of a spring.

moment the coil it enters the fields of force produced by the exciting coil 0 in the end of the gun-barrel, an induction current is produced in coil 72.. This flows in part through the ignition coil 6 and the other part through the closing contact t to the condenser and places this condenser in a loaded or charged condition. Due to the current flowing in the ignition coil z'the iron core l Will be pulled into the coil and thereby presses the spring m together and at the same time swings the lever o in the direction of the arrow at. Thereby the contact piece or member which is secured to the toothed rod p strikes an abutment on the projectile body and thereby is rocked out of its heretofore safe position, that is open position, into a position whereby the lower portion, which is constructed as a rigid member, moves into the position above the heretofore open contacts from the condenser In to the primer 1- in the circuits 8', so that upon the return of the toothed rod p the circuit will be closed by the bridging of the member 9. As soon as the ignition coil h, during the further flight of the projectile, is through and past the field of the exciting coil 0, the induction circuit and therewith the magnetic operation of the coil a on the core I will cease. At the same time, the firing At the speed has been lowered to such an extent that the contact t will be opened again under the action of its spring and the condenser It will maintain its charge since it is now disconnected from the coilsz' and h. The core Z will thereby be moved again as heretofore. Under the action of spring m the core Z moves outwardly beyond coil 21, takes with it the rack p and shifts the contact piece q toward the contact points of the wires .3 leading from the condenser is to the primer 1-. This motion of the rack p and of contact piece 11 is retarded by the fact, that now a pair of wings no is rotated by rack 19 through the intermediary of a gear u. Upon the wiring a being closed thereafter by contact piece g, the condenser is discharged and a spark is produced between the poles embedded in the primer 1' which is thereby ignited.

The strength of the electromotive force produced in the coil 72. and acting in the coil '11 depends on the strength of the field produced y the exciting coil 0 mounted on the gunbarrel. The greater this strength in the exciting coil 0 is, the more the iron core I of the fuse is attracted into the magnet coil 13 and the more time 'passes until the circuit comprising the condenser 70 and the initial ignition 1' is closed after the projectile has passed through the exciting coil 0.

The regulating resistance circuit leading to the excitin scale which permits to read 0 of ignition for each adjusted stren h of resistance and for each fuse used. hisscale may conveniently be arranged on the amperemeter 6 interposed in the circuit leading to the exciting coil 0, so that variations of the current supplied from the source f and therewith variations of the moments of ignition may be seen at once and may be compensated for. by inserting more or less resistance, to obtain the desired moment of ignition.

What we claim and desire to secure by Letters Patent, is a 1. The method of supplying electric energy to electric projectile fuses carrying wit them in an electric storage device a portion of the electric energy required for igniting the the primer, consisting in transmitting to the electric igniting devlce of the projectile the d enclosed in the coil 0 has a the moments remainder of electric energy required for provoking s'aid action, from a source of current separate from the projectile and after the projectile has been fired.

2. The method of supplying electric energy to electric projectile fuses equipped with an electric generator adapted to roduce a part of the electric energy required or igniting the primer, consisting in transmitting to the elecinduction t tion of said i 3. A. gun-barrel and a projectile adapted to be fired thereby and having an electric igniting device, and an electric conductor arranged near the path of the projectile and adapted to actuate by induction the igniting device of the projectile passing past it during flight.

4. A gun-barrel and a projectile adapted to be fired thereby and having an electric igniting device, and means for producing near the path of the projectile a field of electric lines of force to be crossed by the projectile during its flight, to actuate by induction the igniting device of the projectile,

5. A gun-barrel and a "projectile adapted to be fired thereby and having an electric igniting device, and means for producing before the muzzle of said un-bar'rel a field of electric lines of force a aptedto be crossed by said pro'ectile during flight, to actuate by l e igniting device of the project1 e.

6. A gun-barrel and a. projectile adapted to be fired thereby and having an electric igniting device, an electric conductor arranged near the path of the projectile and adapted to actuate by induction the igniting device of the projectile passing past it during flight, and means for varying the electric energy produced by said conductor, to vary the aciting device.

8. A gunarrel and a projectile adapted to be fired thereby and having an electric time fuse adapted to be actuated differently by electric energy of diflerent strength, means, for producing in the path of the projectile a field of electric lines of force adapted to be h crossed by the projectile during flight, to

actuate by induction said time fuse, and means for var in the electric energy produced by said e1 to vary the'timing action of said time fuse.

In testimony whereof, we have signed our signatures. I

HERMANN SCHULER. ANTON GIETMANN.

' trio igniting device of the projectile the remainder of electric energy required for provoking said action, from a source of current separate from the rcg'ectile and after the projectile has been r 

